ZF 6HP21 Reference Documents

I have a 2007 6AT 335i and have been very curious about this transmission and its capabilities. I have collected a few documents that I think should be located in a central place to allow people with a desire to learn more about their transmissions do so. Please add more information if it is available to you.

I have a 2007 6AT 335i and have been very curious about this transmission and its capabilities. I have collected a few documents that I think should be located in a central place to allow people with a desire to learn more about their transmissions do so. Please add more information if it is available to you.

It has 6HP19Z:
realoem.com /bmw/showparts.do?model=VB73&mospid=49550&btnr=24_1024& hg=24&fg=05

For what it's worth, while I was changing my trans pan/filter and fluid, I noticed the transmission has a plate on the side that has the serial number, parts list number and model number.

I can tell you 100% that even though realoem.com says I too have a 6HP19Z, the transmission in my car is a 6HP21. From what I have read, the 'Z' suffix denotes the transmission is for a BMW, and the 6HP19 is the first generation six speed automatic from ZF. I think realoem is wrong.

When in doubt, crawl under the car and look at the transmission itself. That is only 100% sure way to know. This is how I know 100% that my car has a 6HP21 despite realoem.com claiming it has a 6HP19Z.

The ZF 19hp has received an update which is named a zf hp19TU (Technical update in German) and that one goes also under the name hp21.... The hp19Z I do not know but I assume it is the TU and so the 21....

@Sticky, can we sticky this thread, I'm seeing repeated links in other threads to pages already linked to here. Maybe it could be merged with the tech manual thread for the engine, just making a general technical reference thread.

Realoem is not wrong, as it has data fetched directly from the BMW EPC system (further integrated with their PLM system). In fact I found this:
and from my perspective it's clarifies everything.

Yes, but RealOEM claims 6HP19Z not 6HP19TU. As stated, the 6HP19 is the first generation 6 speed automatic. The 6HP19TU and 6HP21 are both designations for the second generation 6 speed automatic which has a higher torque rating. The 6HP19Z is the designation for the first generation 6 speed automatic in a BMW specifically.

Notice how RealOEM tells us the transmission in an E60 530i with a build date of 10/04 is the GA6HP19Z. This car has an N52.

Then RealOEM also tells us that in an E90 335i with a build date of 10/06, the GA6HP19Z is used behind an N54 engine.

RealOEM goes on to claim an E90 LCI 335i with a build date of 10/11 has the GA6HP19Z as well, this time with the N55 engine

This cannot be true.

Now we know that these three cars do not use the same transmissions, so RealOEM must be wrong. We know this because the first generation 6HP's were produced from 2000-2005, and the second generation from 2006-present as far as I can tell. The point is a car built in '04 will not have the same transmission as a car built in '06 or '11 because the generations do not overlap.

If you look around you'll see the 6HP19 has a torque capacity of 295 ft. lbs. and the 6HP21 (6HP19TU) has a torque capacity of 332 ft. lbs. The N55 has a torque output of 300 ft. lbs. The N54 has a torque output of 295 ft. lbs. The N52 has a torque output of 220 ft lbs. So it makes sense to pair the engine with the less torque to the transmission that is rated at less torque. Furthermore, if BMW used the 6HP19(Z) with the N55 as RealOEM claims, they would be exceeding the transmission manufacturer's maximum input torque specification. This is highly unlikely.

So can we finally put this to bed? All E90/E91/E92/E93 335s (i or xi) with six speed autos have the 6HP21 aka the 6HP19TU. This car was never equipped with the 6HP19(Z), ever.

So can we finally put this to bed? All E90/E91/E92/E93 335s (i or xi) with six speed autos have the 6HP21 aka the 6HP19TU. This car was never equipped with the 6HP19(Z), ever.

RealOEM is wrong

Right, your analysis clarifies a lot, thanks. One important thing: Part name/number are two different things. BMW does not claims that in all cars the transmission is the same, they just named it the same. Part No. is changed with every released update. Please note that part numbers are used to identify the part and in examples you've provided it differs for each model. I promise not to bring the subject again

Right, your analysis clarifies a lot, thanks. One important thing: Part name/number are two different things. BMW does not claims that in all cars the transmission is the same, they just named it the same. Part No. is changed with every released update. Please note that part numbers are used to identify the part and in examples you've provided it differs for each model. I promise not to bring the subject again

I understand, but the confusion comes from BMW using the description "GA6HP19Z" for cars from early 2000 up to present day.

This happens all the time at work, the descriptions for our parts are ludicrous sometimes. The reason for this is because the engineers who know better aren't in charge of the part numbering system. It's like a line between engineering and manufacturing where a lot of knowledge gets lost.

Hi,
So I've been a lurker for couple months on this forum as I am afraid I don't have much to bring on the table compared to a lot of people here.
On the topic - I've read all the documents posted here. I've noticed couple places offer mechatronic rebuild kits - Sonnax the ZIP kit, then solenoid kits available at multiple places. However, all (or nearly all) vendors mention adaptation reset after valve body rebuild.
Is this the normal reset done with say INPA or BT cable, and driving to adapt or something different? I am asking as I read that this can mostly be done at the dealer so it makes me wonder if the TCU is keeping logs that cannot be reset with INPA and modifying variables based on expected wear?

Hi,
So I've been a lurker for couple months on this forum as I am afraid I don't have much to bring on the table compared to a lot of people here.
On the topic - I've read all the documents posted here. I've noticed couple places offer mechatronic rebuild kits - Sonnax the ZIP kit, then solenoid kits available at multiple places. However, all (or nearly all) vendors mention adaptation reset after valve body rebuild.
Is this the normal reset done with say INPA or BT cable, and driving to adapt or something different? I am asking as I read that this can mostly be done at the dealer so it makes me wonder if the TCU is keeping logs that cannot be reset with INPA and modifying variables based on expected wear?

I would expect the adaptations to be resettable with INPA. The BT cable may also be able to do it as you describe. I doubt there are any adaptations that INPA cannot reset but the dealer can considering INPA is (was?) dealer software.

I would expect the adaptations to be resettable with INPA. The BT cable may also be able to do it as you describe. I doubt there are any adaptations that INPA cannot reset but the dealer can considering INPA is (was?) dealer software.

Good point about INPA considered dealer software. The part that really bothers me is mentioned in the Sonnax Technical Booklet under electronics:

"The TCM is capable of limited solenoid adaptation without reprogramming."

Also, I'd assume by reprograming they mean flashing / updating firmware for the target car with files from SP-DATEN in this case?

Good point about INPA considered dealer software. The part that really bothers me is mentioned in the Sonnax Technical Booklet under electronics:

"The TCM is capable of limited solenoid adaptation without reprogramming."

Also, I'd assume by reprograming they mean flashing / updating firmware for the target car with files from SP-DATEN in this case?

I would think that statement from Sonnax refers to the stock TCU software's ability to adjust the shifting characteristics via the solenoids. I wouldn't necessarily think Sonnax means reprogramming with BMW software (SP-DATEN). They could just mean programming with a different software.